This invention relates to a reciprocating motion generating apparatus in which the amplitude and the phase of reciprocating motion can be varied.
While a number of mechanisms for converting rotary movements into reciprocating motions have been proposed a cam mechanism is the typical one of such mechanisms. In a widely used cam mechanism comprises a cam having a constant diameter and two rollers or contact pieces engaging the periphery of the cam so that the cam rotates, the rollers are oscillated to cause rods connected to the roller to reciprocate. While this cam mechanism can produce reciprocating or swinging motion since the eccentricity of the cam is constant, it is impossible to adjust the amplitude and the phase of the reciprocating motion. Accordingly, it is necessary to add independently adjusting mechanism which not only increases the cost but also noise generated by the mechanism.